JPH112105A - Combined cycle power generation plant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To sufficiently heat the fuel, and to surely prevent the steaming, by comprising a turbine steam extraction system for supplying the turbine steam extraction of a steam turbine to a fuel heating unit, and a turbine steam extraction recovering system for recovering the turbine steam extraction to the steam turbine, after the fuel, is heated in the fuel heating unit. SOLUTION: A steam turbine 29 supplies the turbine steam extraction during the expansion work, from a steam extraction port 39 to a fuel heating unit 25 through a turbine steam extraction system 40, so that the fuel F of the fuel heating unit 25 is heated by the turbine steam extraction, and then the turbine steam extraction as drain, is circulated to a recovering port 42 through a turbine steam extraction recovering system 41. By using the turbine steam extraction of the steam turbine 29 as a heating source of the fuel F in the fuel heating unit 25, detecting a temperature of the fuel F heated by the fuel heating unit 25 by a temperature gauge 44, and adjusting a turbine steam extraction adjusting valve 43 mounted on the turbine steam extraction system, on the basis of the computing of the temperature by a computing unit 45, the fuel F can be supplied to a gas turbine combustor 26 in a condition that the temperature of the fuel F is properly adjusted without overheating.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combined cycle power plant, and more particularly to a combined cycle power plant in which fuel to be injected into a gas turbine combustor of a gas turbine plant is preliminarily heated to increase the calorific value to improve plant thermal efficiency. It relates to a cycle power plant.

[0002]

2. Description of the Related Art A recent thermal power plant has a shorter start-up operation time than a conventional power plant.
Combined cycle power plants with high plant thermal efficiency are becoming mainstream. This combined cycle power plant combines a gas turbine plant with a steam turbine plant and an exhaust heat recovery boiler, and uses the exhaust heat (exhaust gas) generated from the gas turbine plant to generate steam using the exhaust heat recovery boiler. Is supplied to a steam turbine plant to generate electricity.
There is a configuration shown in FIG.

[0003] The combined cycle power plant 1 comprises:
The configuration includes a gas turbine plant 2, a steam turbine plant 3, and an exhaust heat recovery boiler 4.

The gas turbine plant 2 includes an air compressor 5, a gas turbine combustor 6, and a gas turbine 7. The air AR sucked by the air compressor 5 is pressurized, and fuel is added to the high-pressure air to perform gas turbine combustion. A combustion gas is generated in a gas turbine 6 and the combustion gas is used as a driving gas in a gas turbine 7.
Is to be driven.

The exhaust heat recovery boiler 4 communicates with a superheater 8 and a steam drum 9 arranged from upstream to downstream along the flow of exhaust heat (exhaust gas) from the gas turbine 7. The evaporator 10 and the economizer 11 are accommodated in a casing 12, and water supplied from the steam turbine plant 3 is supplied to the economizer 11.
The heated water (water supply after heating) is flow-controlled by the control valve 13 and then guided to the steam drum 9 where it is naturally circulated in the evaporator 10 by utilizing the specific gravity of the heated water to obtain saturated steam. Then, the saturated steam is heated again by the superheater 8 to generate superheated steam, and the superheated steam is supplied to the steam turbine plant 3 as turbine driving steam.

On the other hand, the steam turbine plant 3 includes a steam turbine 15, a condenser 16, a condensate pump 17, and a feed water pump 18 which are directly connected to a power generator 14, and a waste heat recovery boiler 4
The turbine drive steam supplied from the turbine is expanded by a steam turbine 15, and the generator 14 is driven by the rotational torque generated during the expansion work to generate an electric output.

[0007] The steam turbine plant 3 converts the turbine exhaust gas having completed the expansion work in the steam turbine 15 into a condenser 1.
The condensed water is condensed at 6, and the condensed water is pressurized by a condensate pump 17 to be supplied water, and the supplied water is pressurized again by a water supply pump 18 and returned to the exhaust heat recovery boiler 4.

As described above, in the conventional combined cycle power plant 1, the Brayton cycle of the gas turbine plant 2 and the Rankine cycle of the steam turbine plant 3 are skillfully combined, and the plant heat efficiency is improved by effectively utilizing the exhaust heat of the gas turbine plant 2. It was higher than that of a conventional power plant.

However, as a technique for further improving the thermal efficiency of the conventional combined cycle power plant 1, Japanese Patent Application Laid-Open No. Hei 2-283803 has already been published.

The technique disclosed in Japanese Patent Application Laid-Open No. 2-283803 focuses on the temperature of feed water heated by the economizer 11 of the exhaust heat recovery boiler 4, and even if there is a change in load, the effect of heat is not affected. This is to improve the thermal efficiency of the plant by skillfully utilizing the small amount of heat energy of the heating water. That is, in this technique, as shown in FIG. 14, a fuel heating device 19 is provided in a gas turbine plant 2, and as a heat source of the fuel heating device 19, the economizer 11 of the exhaust heat recovery boiler 4 which is less affected by load fluctuations. Heating water on the outlet side of, the fuel F is heated, and the latent heat required when the water vapor contained in the fuel evaporates is removed. As a result, the combustion gas is removed at a relatively small fuel flow rate by increasing the calorific value. Generates and works to improve plant thermal efficiency.

[0011] As described above, in the conventional combined cycle power plant 1, today, when there is a concern about depletion of fossil fuels, efforts have been made to improve the thermal efficiency of the plant by minimizing the fuel consumed.

[0012]

In the conventional combined cycle power plant 1 shown in FIG. 14, when the fuel F is heated by the fuel heating device 19, the heating source thereof is the heating water supplied from the economizer 11. Economizer 11 to ask for
However, the fact that the heat source of the heating water from the economizer 11 is required as a heat source is increased from the prior art, but there are some problems that need to be improved.

Generally, in this type of technical field, the design differential pressure (generally about 1.5 MPa to 2 MPa) of the control valve 13 provided on the inlet side of the steam drum 9 is controlled by the fuel heating device 1.
9 is larger than the required pressure (generally about 0.2 MPa). For this reason, the heating water that has exited the economizer 11
When flowing to the steam drum 9, steaming (a type of evaporation)
It is necessary to set the pressure to a high value obtained by adding the design differential pressure of the control valve 13 and the safety coefficient to the saturation pressure with respect to the temperature of the heated water itself so as not to generate the pressure.

However, the pressure of the heating water supplied to the fuel heating device 19 should be a value obtained by adding a safety factor to about 0.2 MPa even if the prevention of steaming is considered. Is itself wasteful, and causes unnecessary power consumption of the water supply pump 18.

The heating water as a heating source required by the fuel heating device 19 should be set to a temperature (generally about 150 ° C. to 200 ° C.) obtained by adding about 50 ° C. to the temperature of the heated fuel. However, the temperature of the heated water leaving the economizer 11 is originally set from the heat balance of the entire plant, regardless of the fuel heating. For this reason,
The temperature of the heated water on the heat balance is increased by the amount of fuel heating, and the saturation pressure based on the increase in the temperature is also increased, and a high boosting power of the water supply pump 18 is required, resulting in an increase in cost.

Further, as in the case of the partial load operation, when the amount of heating water supplied to the fuel heating device 19 decreases, the amount of water supplied through the economizer 11 also decreases. The internal pressure rises, and therefore, the heating water that has exited the economizer 11 exceeds the saturation temperature, and there is a possibility that steaming may occur.

As described above, in the conventional combined cycle power plant 1 shown in FIG. 14, while improving the plant thermal efficiency, there are some problems described above.

The present invention has been made in view of such circumstances, and it has been made possible to sufficiently heat the fuel without setting the heating water used for heating the fuel to a high pressure, and to ensure the occurrence of steaming. It is an object of the present invention to provide a combined cycle power generation plant that can prevent the occurrence of such problems.

[0019]

SUMMARY OF THE INVENTION A combined cycle power plant according to the present invention has the following objects.
As described in claim 1, a gas turbine plant is combined with a steam turbine plant and an exhaust heat recovery boiler,
In a combined cycle power plant including a fuel heating device for heating fuel supplied to a gas turbine combustor of the gas turbine plant, a turbine bleed system for supplying turbine bleed air of a steam turbine of the steam turbine plant to the fuel heating device. A turbine bleed air recovery system for recovering the turbine bleed air heated by the fuel of the fuel heating device to the steam turbine.

In order to achieve the above object, the combined cycle power plant according to the present invention, as described in claim 2, has a turbine bleed system including a turbine bleed control valve and a fuel bleed at the outlet side of the fuel heating device. An arithmetic unit is provided for detecting a temperature and controlling opening and closing of the turbine bleed control valve based on a fuel temperature detection signal.

According to a third aspect of the present invention, there is provided a combined cycle power plant comprising a gas turbine plant combined with a steam turbine plant and an exhaust heat recovery boiler. In a combined cycle power plant including a fuel heating device for heating fuel supplied to a turbine combustor, a turbine bleed system for supplying turbine bleed air of a steam turbine of the steam turbine plant to the fuel heating device; and A turbine bleed recovery system for recovering the turbine bleed air heated fuel in the condenser of the steam turbine plant.

In order to achieve the above object, a combined cycle power plant according to the present invention is a combination of a gas turbine plant with a steam turbine plant and an exhaust heat recovery boiler. In a combined cycle power plant including a fuel heating device for heating fuel supplied to a turbine combustor, a turbine bleed system for supplying turbine bleed air of a steam turbine of the steam turbine plant to the fuel heating device; and A turbine bleed air recovery system for recovering turbine bleed air heated fuel at the outlet side of the condensate pump of the steam turbine plant.

According to a fifth aspect of the present invention, there is provided a combined cycle power plant comprising a gas turbine plant combined with a steam turbine plant and an exhaust heat recovery boiler. In a combined cycle power plant including a fuel heating device for heating fuel supplied to a turbine combustor, a first turbine bleed system and a second turbine bleed system for supplying turbine bleed air of a steam turbine of the steam turbine plant to the fuel heater. And a first turbine bleed air recovery system and a second turbine bleed air recovery system that allow the steam turbine to recover the turbine bleed air that has heated the fuel of the fuel heating device.

In order to achieve the above object, the combined cycle power plant according to the present invention is configured such that the first turbine bleed system is provided with the first turbine bleed system during the partial load operation.
Opening the stop valve to use when supplying turbine bleed air to the fuel heating device from the upstream side of the steam turbine,
The second turbine bleed system is used to open the second stop valve during rated operation and supply turbine bleed air to the fuel heating device from the downstream side of the steam turbine.

In order to achieve the above object, the combined cycle power plant according to the present invention has a first turbine bleed system including a first turbine bleed control valve and a fuel heating device. The fuel temperature signal detected at the outlet side is compared with the turbine bleed temperature signal,
In the case where a deviation is found, a calculator is provided for giving a valve opening / closing signal to the first turbine bleed control valve based on the deviation.

In order to achieve the above object, the combined cycle power plant according to the present invention has the second turbine bleed system including the second turbine bleed control valve and the fuel heating device. The fuel temperature signal detected at the outlet side is compared with the turbine bleed temperature signal,
In the case where a deviation is found, a calculator is provided for giving a valve opening / closing signal to the second turbine bleed control valve based on the deviation.

[0027] In order to achieve the above object, the combined cycle power plant according to the present invention, as set forth in claim 9, wherein the first turbine bleed recovery system includes a first turbine bleed recovery stop valve. The structure is such that the turbine bleed recovery stop valve is linked to the first stop valve to control the opening and closing of the valve.

In order to achieve the above object, the combined cycle power plant according to the present invention, as described in claim 10, wherein the second turbine bleed air recovery system includes a second turbine bleed air recovery stop valve. The stop valve is linked to the second turbine bleed control valve to control the opening and closing of the valve.

In order to achieve the above object, the combined cycle power plant according to the present invention is a combination of a gas turbine plant with a steam turbine plant and an exhaust heat recovery boiler. In a combined cycle power plant including a fuel heating device for heating fuel supplied to a turbine combustor, a first turbine turbine of the steam turbine plant is supplied with turbine bleed air to the fuel heating device.
In addition to a turbine bleed system and a second turbine bleed system, a turbine bleed recovery system for recovering turbine bleed air heated fuel of the fuel heating device to the condenser of the steam turbine plant is provided.

In order to achieve the above object, the combined cycle power plant according to the present invention is a combination of a gas turbine plant with a steam turbine plant and an exhaust heat recovery boiler. In a combined cycle power plant including a fuel heating device for heating fuel supplied to a turbine combustor, a first turbine turbine of the steam turbine plant is supplied with turbine bleed air to the fuel heating device.
A turbine bleed system including a turbine bleed system and a second turbine bleed system, and a turbine bleed recovery system for recovering turbine bleed air heated fuel of the fuel heating device to an outlet side of a condensate pump of the steam turbine plant. .

In order to achieve the above object, a combined cycle power plant according to the present invention combines a gas turbine plant with a steam turbine plant and an exhaust heat recovery boiler, and In a combined cycle power plant including a fuel heating device for heating fuel supplied to a turbine combustor, a turbine bleed system for supplying turbine bleed air of a steam turbine of the steam turbine plant to the fuel heating device; and A turbine bleed air recovery system for recovering turbine bleed air that has heated fuel to the steam turbine, a cooler provided in the turbine bleed system, and cooling water supplied to the cooler is supplied to an outlet of a condensate pump of the steam turbine plant. Turbine bleed air with the cooling water system provided on the Retirement was the cooling water, in which a cooling water recovery system for recovering the inlet side of the feedwater pump of the steam turbine plant.

In order to achieve the above object, the combined cycle power plant according to the present invention has a cooling water recovery system including a cooling water recovery control valve and a cooling water recovery control valve. The cooling water recovery control valve is provided with a computing unit for giving a valve opening / closing signal based on the turbine bleed temperature signal.

In order to achieve the above object, the combined cycle power plant according to the present invention is a combination of a gas turbine plant with a steam turbine plant and an exhaust heat recovery boiler. In a combined cycle power plant including a fuel heating device for heating fuel supplied to a turbine combustor, a turbine bleed system for supplying turbine bleed air of a steam turbine of the steam turbine plant to the fuel heating device; and A turbine bleed air recovery system for recovering turbine bleed air heated fuel in the condenser of the steam turbine plant, a cooler provided in the turbine bleed system, and cooling water supplied to the cooler; A cooling water system provided on the outlet side of the condensate pump; The cooling water which has a turbine bleed air is cooled,
A cooling water recovery system for recovering the water at an inlet side of a water supply pump of the steam turbine plant.

In order to achieve the above object, the combined cycle power plant according to the present invention is a combination of a gas turbine plant with a steam turbine plant and an exhaust heat recovery boiler. In a combined cycle power plant including a fuel heating device for heating fuel supplied to a turbine combustor, a turbine bleed system for supplying turbine bleed air of a steam turbine of the steam turbine plant to the fuel heating device; and A turbine bleed air recovery system for recovering turbine bleed air heated fuel at the inlet side of a water supply pump of the steam turbine plant, a cooler provided in the turbine bleed system, and cooling water supplied to the cooler. Cooling water system installed on the outlet side of the condensate pump of the plant The cooling water that has cooled the turbine extraction above the cooler, in which a cooling water recovery system for recovering the inlet side of the feedwater pump of the steam turbine plant.

In order to achieve the above object, the combined cycle power plant according to the present invention combines a gas turbine plant with a steam turbine plant and an exhaust heat recovery boiler to achieve the above object. In a combined cycle power plant including a fuel heating device for heating fuel supplied to a turbine combustor, a first turbine turbine of the steam turbine plant is supplied with turbine bleed air to the fuel heating device.
A turbine bleed system, a second turbine bleed system, a first turbine bleed recovery system and a second turbine bleed recovery system for recovering the turbine bleed heated fuel of the fuel heating device to the steam turbine, and the first turbine bleed system And a cooler provided in the second turbine extraction system, and cooling water supplied to the cooler is cooled by a cooling water system provided on the outlet side of a condensate pump of the steam turbine plant and the cooler. A cooling water recovery system for recovering cooling water at an inlet side of a water supply pump of the steam turbine plant.

In order to achieve the above object, a combined cycle power plant according to the present invention combines a gas turbine plant with a steam turbine plant and an exhaust heat recovery boiler to achieve the above object. In a combined cycle power plant including a fuel heating device that heats fuel supplied to a turbine combustor, a turbine extraction system that supplies a turbine bleed air of a steam turbine of the steam turbine plant to the fuel heating device; A first turbine extraction system and a second turbine extraction system for supplying turbine extraction air of a steam turbine to the fuel heating device, and a turbine for recovering the turbine extraction air heating the fuel of the fuel heating device to a condenser of the steam turbine plant The bleed air recovery system and the first turbi A cooler provided in the bleed system and the second turbine bleed system, cooling water supplied to the cooler is supplied to a cooling water system provided on an outlet side of a condensate pump of the steam turbine plant, and turbine bleeding is performed by the cooler. A cooling water recovery system for recovering the cooled cooling water at an inlet side of a feed pump of the steam turbine plant.

In order to achieve the above object, a combined cycle power plant according to the present invention combines a gas turbine plant with a steam turbine plant and an exhaust heat recovery boiler to achieve the above object. In a combined cycle power plant including a fuel heating device that heats fuel supplied to a turbine combustor, a turbine extraction system that supplies a turbine bleed air of a steam turbine of the steam turbine plant to the fuel heating device; A first turbine extraction system and a second turbine extraction system for supplying turbine bleed air of the steam turbine to the fuel heating device, and turbine bleed air heated fuel of the fuel heating device is recovered at an inlet side of a water supply pump of the steam turbine plant. Turbine bleed air recovery system A cooler provided in the first turbine bleed system and the second turbine bleed system, cooling water supplied to the cooler is supplied to a cooling water system provided on an outlet side of a condensate pump of the steam turbine plant, A cooling water recovery system for recovering the cooling water that has cooled the turbine bleed air at the inlet side of the water supply pump of the steam turbine plant.

[0038]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a combined cycle power plant according to the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic system diagram showing a first embodiment of a combined cycle power plant according to the present invention.

The combined cycle power plant 20 according to the present embodiment includes a gas turbine plant 21, a steam turbine plant 22, and an exhaust heat recovery boiler 23.

The gas turbine plant 21 includes an air compressor 24, a fuel heating device 25, a gas turbine combustor 26, and a gas turbine 27. The air AR sucked by the air compressor 24 is pressurized, and the high pressure air is heated by the fuel. The combustion fuel is generated by the gas turbine combustor 26 by adding the heated fuel from the device 25, and the gas turbine 27 is driven using the combustion gas as a driving gas.

The steam turbine plant 22 includes a steam turbine 29 directly connected to a generator 28, a condenser 30, a condensate pump 31, and a feedwater pump 32. The turbine drive steam supplied from the exhaust heat recovery boiler 23 is provided. The steam turbine 2
9, the expansion work is performed, and the generator 28 is rotationally driven by the rotational torque generated at the time of the expansion work to obtain an electric output. On the other hand, the turbine exhaust that has completed the expansion work is condensed by the condenser 30 and condensed. The condensed water is pressurized by a condensate pump 31 to be supplied water, and the supplied water is pressurized again by a water supply pump 32 to be returned to the exhaust heat recovery boiler 23.

On the other hand, the exhaust heat recovery boiler 23 communicates with a superheater 33 and a steam drum 34 arranged from upstream to downstream along the flow of exhaust heat (exhaust gas) from the gas turbine 27. The evaporator 35 and the economizer 36 are accommodated in a casing 37, and the feed water from the steam turbine plant 22 is heated by the economizer 36, and the heated water is flow-controlled by the control valve 38 and then guided to the steam drum 34. Here, the specific gravity of the heated water is used to naturally circulate in the evaporator 35 to produce saturated steam, and the saturated steam is heated again by the superheater 33 to generate superheated steam, and the superheated steam is used as turbine driving steam. It is supplied to the turbine plant 22.

The steam turbine 29 includes a turbine bleed system 40 for supplying turbine bleed during expansion work from the bleed port 39 to the fuel heating device 25.
After the fuel F of the fuel heating device 25 is heated by the turbine bleed air supplied by 0, the turbine bleed air as a drain is returned to the recovery port 42 via the turbine bleed air recovery system 41.

Further, while the turbine bleed system 40 is provided with a bleed control valve 43, a fuel temperature signal detected by a thermometer 44 provided on the outlet side of the fuel heating device 25 is calculated by a calculator 45 into a valve opening / closing signal. The turbine bleed control valve 43 is opened and closed according to the operation signal to control the flow rate of the turbine bleed.

As described above, in the present embodiment, the heating source of the fuel F of the fuel heating device 25 is obtained from the turbine bleed of the steam turbine 29, and the turbine bleed system 40 is provided with the turbine bleed control valve 43. Since the temperature of the fuel F heated at 25 is detected by the thermometer 44, the detection signal is calculated by the calculator 45, and the calculation signal is given to the turbine bleed control valve 43 to control the valve opening.
The fuel F can be adjusted to an appropriate temperature and supplied to the gas turbine combustor 26 without overheating.

Further, in this embodiment, even when the fuel F passing through the fuel heating device 25 is small, as in the partial load operation, the turbine bleed is controlled by the turbine bleed control valve 43 so that the fuel F
Because the flow rate is controlled to match the flow rate of
The occurrence of steaming of the fuel heating device 25 can be reliably prevented.

Therefore, according to the present embodiment, the turbine bleed air supplied to the fuel heating device 25 is controlled so as to match the flow rate of the fuel F together with the prevention of the occurrence of steaming in the fuel heating device 25. Unlike the related art, there is no need to pump up the water supply pump 32, the power consumption of the plant can be reduced, and the thermal efficiency of the plant can be further improved as compared with the related art.

FIG. 2 is a schematic system diagram showing a first example of the first embodiment of the combined cycle power plant according to the present invention.

In the present embodiment, a turbine bleed air recovery system 41 for recovering turbine bleed air after heating the fuel F by the fuel heating device 25 is connected to the condenser 30. Since they are the same as those of the embodiment, the same reference numerals are given and the description is omitted.

In this embodiment, the fuel heating device 25 is connected to the condenser 30 via the turbine bleed gas recovery system 41, so that the degree of vacuum is maintained at the same level as that of the condenser 30 which is evacuated. When the fuel F is heated by the turbine bleed, the heat of the turbine bleed can be fully utilized and the heat exchange can be performed more effectively. The fuel F can be heated by bleeding.

Therefore, in the present embodiment, the fuel F can be heated with a relatively small amount of turbine bleed air due to the specialty of the vacuum, so that the turbine drive steam can be used to increase the output and the plant thermal efficiency can be reduced. Can be improved.

FIG. 3 is a schematic system diagram showing a second example of the first embodiment of the combined cycle power plant according to the present invention. Note that the same reference numerals are given to portions that are the same as or correspond to the components of the first embodiment.

In the present embodiment, a turbine bleed air recovery system 41 for recovering the turbine bleed air after heating the fuel F by the fuel heating device 25 as drain is connected to the outlet side of the condensate pump 31. Reference numeral 46 denotes a pump.

In this embodiment, the turbine bleed air having a relatively high temperature after heating of the fuel F is supplied as a drain to the outlet side of the condensate pump 31 to join the feed water and raise the temperature of the feed water. The amount of steam generated from the steam drum 34 of the boiler 23 can be increased more than before, and the plant thermal efficiency can be further increased based on the increase in the amount of steam.

FIG. 4 is a schematic system diagram showing a third example of the first embodiment of the combined cycle power plant according to the present invention. Note that the same reference numerals are given to portions that are the same as or correspond to the components of the first embodiment.

In the present embodiment, the bleed port 3 of the steam turbine 29
A first turbine bleed system 40a and a second turbine bleed system 40 for supplying turbine bleed from the fuel tanks 9 and 39 to the fuel heating device 25
b, while a plurality of turbine bleed systems 40 are provided, a first turbine bleed recovery system 41 a for heating the fuel F by the fuel heating device 25 and then recovering the turbine bleed air as the drain to the recovery ports 42 and 42 of the steam turbine 29. It is provided with a plurality of turbine bleed recovery systems 41 of a two-turbine bleed recovery system 41b.

In this embodiment, each turbine bleed system 40
a, 40b, each turbine bleed system 40
a and 40b, a first stop valve 47a, a second stop valve 47b, a first turbine bleed control valve 48a, a second turbine bleed control valve 48b, and a first turbine bleed temperature detector 49, respectively.
a, each of the second turbine bleed temperature detectors 49b.

Further, in the present embodiment, the first turbine bleed gas recovery stop valve 50a and the second turbine bleed gas recovery system are provided in each of the turbine bleed air recovery systems 41a and 41b by providing the respective turbine bleed air recovery systems 41a and 41b. Stop valve 50b
Are provided.

In this embodiment, the steam turbine 2
9 can be used as a heating source for the fuel F as turbine bleed air as a turbine bleed, whereby the thermal efficiency of the plant can be made relatively high, and during partial load operation, the turbine drive steam downstream of the steam turbine 29 can be used. It is noted that if the fuel is supplied to the fuel heating device 25 as turbine bleed air, it is difficult to raise the temperature of the fuel F to an appropriate temperature. 25, the second turbine bleed air system 40b on the downstream side of the turbine is used. During partial load operation, when the turbine bleed air from the bleed port 39 of the steam turbine 29 is supplied to the fuel heating device 25, the turbine upstream side is used. The first turbine bleed system 40a is used, and the bleed point is switched corresponding to each operation.

Specifically, at the time of rated operation, the first turbine bleed system 40a fully closes the first stop valve 47a and the first turbine bleed recovery stop valve 50a, while the second turbine bleed system 40b closes the second turbine bleed system 40b. The stop valve 47b and the second turbine bleed air collection stop valve 50b are fully opened. Then, the turbine bleed supplied from the bleed port 39 of the steam turbine 29 to the fuel heating device 25 through the second turbine bleed system 40b heats the fuel F and then drains the second turbine bleed recovery valve 50 as a drain.
b, is recovered at the recovery port 42 of the steam turbine 29 via the second turbine bleed recovery system 41b. At that time, the converter 45
Compares the actual temperature fuel signal detected by the thermometer 44 with the turbine bleed temperature signal detected by the second turbine bleed temperature detector 49b, and calculates a valve opening / closing signal based on the deviation when a deviation occurs. The operation signal is supplied to the second turbine bleed control valve 48b to control the valve opening, thereby controlling the flow rate of the turbine bleed and adjusting the fuel F to an appropriate temperature.

On the other hand, during the partial load operation, contrary to the above, the first turbine bleed system 40a opens the first stop valve 47a and the first turbine bleed recovery stop valve 50a and opens the second turbine bleed system 49b. Completely closes the second stop valve 47a and the second turbine bleed air collection stop valve 50b. Then, the first turbine bleed system 40a supplies the turbine bleed to the fuel heating device 25, and the switch 45 controls the opening degree of the first turbine bleed control valve 48a in the same manner as described above, so that the fuel F is properly adjusted. Adjust to temperature. The switch 45 has a first turbine bleed system 40a depending on the rated operation and the partial load operation.
An automatic switching circuit is incorporated so that the switching between the second turbine extraction system 40b and the second turbine extraction system 40b can be automatically performed.
Further, in the present embodiment, the valve opening / closing control of each of the stop valves 47a and 47b, each of the turbine bleed control valves 48a and 48b, and each of the turbine bleed recovery stop valves 50a and 50b is performed at the turbine bleed temperature and the fuel temperature. It may be performed at the turbine bleed pressure and the fuel pressure. Further, the automatic switching circuit of the switching unit 45 performs the switching operation when the turbine extraction temperature and the fuel temperature become lower than the preset reference values. However, the switching operation may be performed by a load signal.

As described above, in this embodiment, the turbine bleed system 40 for supplying turbine bleed air to the fuel heating device 25 is provided in a plurality of systems and is selectively used depending on the operation state. By heating F to an appropriate temperature, steaming can be prevented, and a more stable plant thermal efficiency can be secured even in a partial load operation as compared with the related art.

FIG. 5 is a schematic system diagram showing a fourth example of the first embodiment of the combined cycle power plant according to the present invention. Note that the same reference numerals are given to portions that are the same as or correspond to the components of the first embodiment.

This embodiment is similar to the third embodiment of the first embodiment, in that a first turbine bleed system 40 a for supplying turbine bleed air from the bleed ports 39, 39 of the steam turbine 29 to the fuel heating device 25, A plurality of turbine bleed systems 40 of the turbine bleed system 40b are provided, and during rated operation, the second turbine bleed system 40b downstream of the turbine is used, and during partial load operation, the first turbine bleed system 40a upstream of the turbine is used. And, while switching the bleed point corresponding to each operation,
The turbine bleed air as a drain after the fuel F is heated by the fuel heating device 25 is recovered by the condenser 30 via the turbine bleed air recovery system 41.

As described above, in this embodiment, the fuel heating device 25 is provided with a plurality of turbine bleed systems 40 for supplying turbine bleed as a fuel heating source, and can be selectively used in accordance with each operation. At the same time, the fuel heating device 25 is connected to the condenser 30 via the turbine bleed air recovery system 41 so that the degree of vacuum can be maintained at the same level as that of the condenser 30 in a vacuum. In each operation, steaming can be prevented by effectively heating the fuel F with a relatively small amount of turbine bleed air,
Plant thermal efficiency can be improved.

FIG. 6 is a schematic system diagram showing a fifth example of the first embodiment of the combined cycle power plant according to the present invention. Note that the same reference numerals are given to portions that are the same as or correspond to the components of the first embodiment.

This embodiment is similar to the third embodiment of the first embodiment, in that a first turbine bleed system 40 a for supplying turbine bleed air from the bleed ports 39, 39 of the steam turbine 29 to the fuel heating device 25, A plurality of turbine bleed systems 40 of the turbine bleed system 40b are provided, and during rated operation, the second turbine bleed system 40b downstream of the turbine is used, and during partial load operation, the first turbine bleed system 40a upstream of the turbine is used. And, while switching the bleed point corresponding to each operation,
The turbine bleed air as a drain after heating the fuel F by the fuel heating device 25 is supplied to the turbine bleed air recovery system 41 and the pump 4.
6 and collected at the outlet side of the condensate pump 31.

As described above, in the present embodiment, the fuel heating device 25 is provided with a plurality of turbine bleed systems 40 for supplying turbine bleed as a fuel heating source, and can be selectively used in accordance with each operation. At the same time, the turbine bleed air as a drain is recovered from the fuel heating device 25 via the turbine bleed air recovery system 41 and the pump 46 to the outlet side of the condensate pump 31 to raise the temperature of the water supply. The fuel F can be effectively heated by the bleeding, and the steam drum 34 of the exhaust heat recovery boiler 23
The amount of steam from the fuel can be increased more.

FIG. 7 is a schematic system diagram showing a second embodiment of the combined cycle power plant according to the present invention. Note that the same reference numerals are given to portions that are the same as or correspond to the components of the first embodiment.

In this embodiment, the bleed port 3 of the steam turbine 29 is
9, the temperature of the turbine bleed air supplied to the fuel heating device 25 via the turbine bleed control valve 43 of the turbine bleed system 40 is high, and the fuel F of the fuel heating device 25 may exceed the allowable temperature and pressure and spontaneously ignite. In consideration of the case, a cooler 51 is provided in the turbine bleed system 40.

This cooler 51 is provided with a cooling water system 52 that bypasses the outlet side of the condensate pump 31 and uses a part of the supply water as cooling water. After cooling the turbine bleed air to an appropriate temperature, the cooling water is cooled. It is designed so that the water can be recovered at the inlet side of the water supply pump 32 via the cooling water recovery control valve 53 of the water recovery system 54.

The cooler 51 is provided with a turbine bleed thermometer 55 at the outlet thereof. When the detected actual turbine bleed temperature exceeds a predetermined reference value, a valve opening / closing signal is generated based on the deviation. , And a converter 56 is provided to supply the operation signal to the cooling water recovery control valve 53 of the cooling water recovery system 54 to control the opening and closing of the valve.

As described above, in the present embodiment, the fuel heating device 25 from the bleed port 39 of the steam turbine 29 via the turbine bleed control valve 43 of the turbine bleed system 40 and the cooler 51.
The fuel F is heated by the turbine bleed air supplied to the steam turbine, and after the heating, the turbine bleed air as the drain is recovered to the recovery port 42 of the steam turbine 29 via the turbine bleed air recovery system 41, and from the outlet side of the condensate pump 31. After cooling the turbine bleed air to an appropriate temperature with the cooling water as a part of the supply water supplied to the cooler 51 via the cooling water system 52, the cooling water is flow-controlled by the cooling water recovery control valve 53 of the cooling water recovery system 54. Then, since the fuel is recovered at the inlet side of the water supply pump 32, the steam contained in the fuel F is evaporated with the heating of the fuel F to lose latent heat, and as a result, the calorific value of the fuel F can be increased. The cooling water can be heated to a relatively high temperature by the heat taken when cooling the turbine bleed air to an appropriate temperature and combined with the water supplied from the condensate pump 31 to increase the temperature of the water.

Therefore, according to the present embodiment, the fuel F
And the heat generated by removing the heat of the turbine bleed air was used to raise the temperature of the feed water, and the amount of steam generated from the steam drum 34 of the exhaust heat recovery boiler 23 was increased. In addition, the plant thermal efficiency can be further improved than before.

FIG. 8 is a schematic system diagram showing a first example of the second embodiment of the combined cycle power plant according to the present invention. The same reference numerals are given to the same or corresponding parts as the components of the first embodiment and the second embodiment.

In this embodiment, similarly to the second embodiment, a cooler 51 is provided in the turbine bleed system 40, and when the temperature of the turbine bleed air is high in the cooler 51, a bypass is made from the outlet side of the condensate pump 31. The turbine bleed air is cooled to an appropriate temperature with cooling water as a part of the supply water of the cooling water system 52, and the cooling water heated at the time of cooling is cooled by the cooling water collection control valve 53 of the cooling water collection system 54.
The turbine bleed air heated by the fuel heating device 25 and heated by the fuel F is recovered by the condenser 30 through the turbine bleed recovery system 41 while being recovered at the inlet side of the water supply pump 32 through the water supply pump 32. Other configurations are the same as those of the first embodiment and the second embodiment, and a description thereof will be omitted.

As described above, in this embodiment, the condensing pump 3
The turbine bleed air is cooled to an appropriate temperature by the cooler 51 using a part of the feed water on the outlet side of 1 as the cooling water, and the cooled heated water is recovered at the inlet side of the feed water pump 32 to raise the temperature of the feed water. At the same time, the above-described turbine bleed air having heated the fuel F by the fuel heating device 25 was recovered by the condenser 30 via the turbine bleed air recovery system 41 to effectively utilize the heat, so that the plant thermal efficiency was improved more than before. It can be further improved.

FIG. 9 is a schematic system diagram showing a second example of the second embodiment of the combined cycle power plant according to the present invention. The same reference numerals are given to the same or corresponding parts as the components of the first embodiment and the second embodiment.

In this embodiment, similarly to the second embodiment, a cooler 51 is provided in the turbine bleed system 40, and when the temperature of the turbine bleed is high in the cooler 51, the water supply from the outlet side of the condensate pump 31 is performed. The turbine bleed air is cooled to an appropriate temperature with the cooling water as a part of the cooling water, and the cooling water heated at the time of cooling is recovered to the inlet side of the water supply pump 32 via the cooling water recovery control valve 53 of the cooling water recovery system 54. At the same time, the above-described turbine bleed air having heated the fuel F by the fuel heating device 25 is recovered at the inlet side of the water supply pump 32 via the pump 46 of the turbine bleed recovery system 41.

As described above, in the present embodiment, the condensing pump 3
The turbine bleed air is cooled to an appropriate temperature by the cooler 51 using a part of the feed water on the outlet side of 1 as the cooling water, and the heated cooling water after cooling is collected at the inlet side of the feed water pump 32 to raise the temperature of the feed water. Further, the turbine bleed air, which has heated the fuel F by the fuel heating device 25, is also recovered at the inlet side of the water supply pump 32 via the pump 46 of the turbine bleed air recovery system 41 to further increase the temperature of the water supply. The amount of steam generated from the steam drum 34 of the heat recovery boiler 23 can be generated more than before.

Therefore, according to the present embodiment, since the heat is effectively used, the thermal efficiency of the plant can be further improved than before.

FIG. 10 is a schematic system diagram showing a third example of the second embodiment of the combined cycle power plant according to the present invention. Note that the first embodiment and the second embodiment
The same reference numerals are given to the same or corresponding parts of the components of the embodiment.

In this embodiment, the turbine bleed system 40 and the turbine bleed recovery system 41 of the third embodiment in the first embodiment shown in FIG. 4 are replaced with the turbine bleed recovery system 41 in the first embodiment in the second embodiment shown in FIG. This is a combination of a cooling water system 52 and a cooling water recovery system 54, and the bleed ports 39, 39 of the steam turbine 29 are provided.
A plurality of turbine bleed systems 40 a and a second turbine bleed system 40 a for supplying turbine bleed to the fuel heater 25 from the fuel heater 25.
The first turbine bleed recovery system 41a and the second turbine bleed recovery system 41b for recovering the turbine bleed air as drain to the recovery ports 42 and 42 of the steam turbine 29 after heating the fuel F by
Of a plurality of turbine bleed air recovery systems 41.

In this embodiment, each turbine bleed system 40
a, 40b, each turbine bleed system 40
a and 40b, a first stop valve 47a, a second stop valve 47b, a first turbine bleed control valve 48a, a second turbine bleed control valve 48b, and a first turbine bleed temperature detector 49, respectively.
a, each of the second turbine bleed temperature detectors 49b.

Further, in this embodiment, the first turbine bleed air recovery stop valve 50a and the second turbine bleed air recovery system are provided in each of the turbine bleed air recovery systems 41a and 41b by providing the respective turbine bleed air recovery systems 41a and 41b. This is provided with each of the stop valves 50b.

In this embodiment, a cooler 51 is provided in the turbine bleed air system 40. When the temperature of the turbine bleed air is high in the cooler 51, the cooling air is bypassed from the outlet side of the condensate pump 31 to cool the cooling water system 52. A cooling water recovery system 54 is provided for cooling the turbine bleed air to an appropriate temperature with cooling water as a part of the water supply through a water control valve 57 and collecting the cooling water heated at the time of cooling at the inlet side of the water supply pump 32. It is a thing.

Further, in this embodiment, the turbine bleed system 40
If the turbine bleed temperature signal detected by the turbine bleed thermometer 55 provided on the outlet side of the cooler 51 accompanying the provision of the cooler 51 has a deviation from a preset reference value, the deviation And a converter 56 for giving a valve opening / closing signal to the cooling water control valve 57 of the cooling water system 52 to control the flow rate of the cooling water as a part of the supply water. Note that other configurations are the same as those of the third example of the first embodiment and the first example of the second embodiment, and thus redundant description will be omitted.

In this embodiment, similarly to the third embodiment of the first embodiment, when the turbine bleed from the bleed port 39 of the steam turbine 29 is supplied to the fuel heating device 25 during the rated operation, the downstream side of the turbine is used. Using the second turbine bleed system 40b to supply turbine bleed air from the bleed port 39 of the steam turbine 29 to the fuel heating device 25 during partial load operation, using the first turbine bleed system 40a on the upstream side of the turbine, The bleed point is switched corresponding to each operation.

At this time, each turbine bleed system 40a, 40b
When the temperature of the turbine bleed air supplied to the fuel heating device 25 from any of the above is high, the cooling water system 52
The cooling water is supplied to the cooler 51 as a part of the supply water on the outlet side of the first cooling device 51, and the turbine bleed air is cooled to an appropriate temperature. At the time of cooling, the heated cooling water is collected at the inlet side of the water supply pump 32. It has become. When cooling the turbine bleed air to an appropriate temperature with the cooler 51, the cooling water system 52 detects the turbine bleed air with a turbine bleed thermometer 55 provided on the outlet side of the cooler 51, and a detection signal thereof is set in advance. If there is a deviation from the reference value, a valve opening / closing signal is calculated by the converter 56 based on the deviation, and the calculated signal is given to the cooling water control valve 57 to control the flow rate of the cooling water. ing.

As described above, in this embodiment, the turbine bleed system 40 for supplying turbine bleed air to the fuel heating device 25 is provided in a plurality of systems so that they can be selectively used according to the operation state, and the temperature of the turbine bleed air is high. At this time, a cooler 51 is provided in the cooling water system 52 to cool the turbine bleed air to an appropriate temperature.
Since it was collected at the inlet side of the water supply pump 32 via 4,
It is possible to prevent the steaming by heating the fuel F of the fuel heating device 25 to an appropriate temperature, to make effective use of heat, and to secure a more stable plant thermal efficiency even in partial load operation than before. Can be.

FIG. 11 is a schematic system diagram showing a fourth example of the combined cycle power plant according to the second embodiment of the present invention. The first embodiment or the second embodiment
Parts that are the same as or correspond to the components of the embodiment are given the same reference numerals.

In this embodiment, the turbine bleed air system 40 and the turbine bleed air recovery system 41 of the fourth embodiment in the first embodiment shown in FIG. 5 are replaced with the turbine bleed air recovery system 41 of the third embodiment in the second embodiment shown in FIG. This is a combination of a cooling water system 52 and a cooling water recovery system 54, and the bleed ports 39, 3 of the steam turbine 29
9 to supply turbine bleed air to the fuel heating device 25
A plurality of turbine bleed systems 40a and 40b are provided, and the second turbine bleed system 40b on the downstream side of the turbine is used during rated operation, and the second turbine bleed system 40b on the downstream side of the turbine during partial load operation. 1 turbine bleed system 40
a, while the bleed point is switched in accordance with each operation, the turbine bleed as the drain after the fuel F is heated by the fuel heating device 25 is collected in the condenser 30 through the turbine bleed recovery system 41. And a turbine bleed recovery system 41 to be used.

In this embodiment, each turbine bleed system 40
a, 40b, each turbine bleed system 40
a and 40b, a first stop valve 47a, a second stop valve 47b, a first turbine bleed control valve 48a, a second turbine bleed control valve 48b, and a first turbine bleed temperature detector 49, respectively.
a, each of the second turbine bleed temperature detectors 49b.

In this embodiment, the turbine bleed air as the drain after the fuel F is heated by the fuel heating device 25 is recovered in the condenser 30 through the turbine bleed recovery system 41.

In this embodiment, a cooler 51 is provided in the turbine bleed air system 40. When the temperature of the turbine bleed air is high in the cooler 51, the cooling air is bypassed from the outlet side of the condensate pump 31 to cool the cooling water system 52. A cooling water recovery system 54 is provided that cools the turbine bleed air to an appropriate temperature with cooling water as a part of the water supply through a water control valve, and recovers the cooling water heated at the time of cooling to the inlet side of the water supply pump 32. Things.

Further, in this embodiment, the turbine bleed system 40
If the turbine bleed signal detected by the turbine bleed thermometer 55 provided on the outlet side of the cooler 51 with the provision of the cooler 51 has a deviation from a preset reference value, the deviation And a calculator 56 for giving a valve opening / closing signal to the cooling water control valve 57 of the cooling water system 52 to control the flow rate of the cooling water as a part of the water supply. Note that other configurations are the same as those of the fourth example of the first embodiment and the third example of the second embodiment, and thus redundant description will be omitted.

In this embodiment, similarly to the third embodiment of the first embodiment, when the turbine bleed from the bleed port 39 of the steam turbine 29 is supplied to the fuel heating device 25 during the rated operation, the downstream side of the turbine is Using the second turbine bleed system 40b to supply turbine bleed air from the bleed port 39 of the steam turbine 29 to the fuel heating device 25 during partial load operation, using the first turbine bleed system 40a on the upstream side of the turbine, The bleed point is switched according to each operation.

At this time, each turbine bleed system 40a, 40b
When the temperature of the turbine bleed air supplied to the fuel heating device 25 from any of the above is high, the cooling water system 52
The cooling water is supplied to the cooler 51 as a part of the supply water on the outlet side of the first cooling device 51 so that the turbine bleed air is cooled to an appropriate temperature. Has become. When cooling the turbine bleed air to an appropriate temperature with the cooler 51, the cooling water system 52 detects the turbine bleed air with a turbine bleed thermometer 55 provided on the outlet side of the cooler 51, and a detection signal thereof is set in advance. If there is a deviation from the reference value, a valve opening / closing signal is calculated by the converter 56 based on the deviation, and the calculated signal is given to the cooling water control valve 57 to control the flow rate of the cooling water. ing.

As described above, in the present embodiment, the turbine bleed system 40 for supplying turbine bleed air to the fuel heating device 25 is provided in a plurality of systems so that they can be selectively used according to the operation state. At this time, the turbine bleed air was cooled to an appropriate temperature by the cooler 51 provided in the turbine bleed system 40, and at the time of cooling, the heated cooling water was recovered to the inlet side of the water supply pump 32 via the cooling water recovery system 54. In addition, it is possible to prevent the steaming by heating the fuel F of the fuel heating device 25 to an appropriate temperature, to effectively utilize the heat, and to secure a more stable plant thermal efficiency even in the partial load operation than before. Can be.

FIG. 12 is a schematic system diagram showing a fifth example of the second embodiment of the combined cycle power plant according to the present invention. The first embodiment or the second embodiment
Parts that are the same as or correspond to the constituent parts of the embodiment are given the same reference numerals.

In this embodiment, the turbine bleed air system 40 and the turbine bleed air recovery system 41 of the fifth embodiment in the first embodiment shown in FIG. 6 are replaced with the turbine bleed air recovery system 41 in the third embodiment in the second embodiment shown in FIG. This is a combination of a cooling water system 52 and a cooling water recovery system 54, and the bleed ports 39, 3 of the steam turbine 29
9 to supply turbine bleed air to the fuel heating device 25
A plurality of turbine bleed systems 40a and 40b are provided, and a turbine bleed system is provided in which the fuel F is heated by the fuel heating device 25 and then the turbine bleed gas as a drain is collected at the inlet side of the water supply pump 32. While a recovery system 41 is provided, a cooling water system 52 that supplies a part of the water supplied from the condensing pump 31 as cooling water to a cooler 51 provided in the turbine bleeding system 40, A cooling water recovery system 54 that recovers the heated cooling water at the inlet side of the water supply pump 32 is provided. Note that other configurations are the same as those of the fifth example of the first embodiment and the third example of the second embodiment, and thus redundant description will be omitted.

As described above, in the present embodiment, the turbine bleed system 40 for supplying the turbine bleed to the fuel heating device 25 is provided in a plurality of systems, and is selectively used in accordance with one of the rated operation and the partial load operation. If the temperature of the turbine bleed is still high, the turbine bleed system 40
The turbine bleed air is cooled to an appropriate temperature by the cooler 51 provided in the
During cooling, the heated cooling water is recovered at the inlet side of the water supply pump 32 via a cooling water recovery system 54, and turbine bleed air as a drain from the fuel heating device 25 is supplied via a turbine bleed air recovery system 41. Since the water is recovered at the inlet side of the pump 32 and the water supply is further increased, the exhaust heat recovery boiler 2
The amount of steam generated from the third steam drum 34 can be generated more than before.

Therefore, according to the present embodiment, since the heat is effectively used, the thermal efficiency of the plant can be further improved as compared with the prior art.

[0105]

As described above, in the combined cycle power plant according to the present invention, the fuel heating source of the fuel heating device is determined by the turbine bleed, and the flow rate of the turbine bleed is controlled to match the fuel flow. Therefore, at the time of heat exchange between turbine bleed air and fuel, steaming in the fuel heating device can be prevented, and the plant thermal efficiency can be greatly improved as compared with the related art.

Further, in the combined cycle power plant according to the present invention, the turbine bleed for heating the fuel of the fuel heating device can be selectively used for the rated operation and the partial load operation. Plant thermal efficiency can be secured.

In the combined cycle power plant according to the present invention, when the turbine bleed for heating the fuel of the fuel heating device is high, the turbine bleed is cooled to an appropriate temperature, so that the fuel is heated in a stable state. It is possible to prevent occurrence of an unexpected accident such as ignition.

Further, the combined cycle power plant according to the present invention aims to recover heat by heating at least one of the turbine bleed air after heating the fuel and the heat of the cooling water after cooling the turbine bleed air to an appropriate temperature. Therefore, stable plant thermal efficiency can be ensured.

[Brief description of the drawings]

FIG. 1 is a schematic system diagram showing a first embodiment of a combined cycle power plant according to the present invention.

FIG. 2 is a schematic system diagram showing a first example of the first embodiment of the combined cycle power plant according to the present invention.

FIG. 3 is a schematic system diagram showing a second example of the first embodiment of the combined cycle power plant according to the present invention.

FIG. 4 is a schematic system diagram showing a third example of the first embodiment of the combined cycle power plant according to the present invention.

FIG. 5 is a schematic system diagram showing a fourth example of the first embodiment of the combined cycle power plant according to the present invention.

FIG. 6 is a schematic system diagram showing a fifth example of the first embodiment of the combined cycle power plant according to the present invention.

FIG. 7 is a schematic system diagram showing a second embodiment of a combined cycle power plant according to the present invention.

FIG. 8 is a schematic system diagram showing a first example of the combined cycle power plant according to the second embodiment of the present invention.

FIG. 9 is a schematic system diagram showing a second example of the combined cycle power plant according to the second embodiment of the present invention.

FIG. 10 is a schematic system diagram showing a third example of the combined cycle power plant according to the second embodiment of the present invention.

FIG. 11 is a schematic system diagram showing a fourth example of the combined cycle power plant according to the second embodiment of the present invention.

FIG. 12 is a schematic system diagram showing a fifth example of the combined cycle power plant according to the second embodiment of the present invention.

FIG. 13 is a schematic system diagram showing an embodiment of a conventional combined cycle power plant.

FIG. 14 is a schematic system diagram showing another embodiment of the conventional combined cycle power plant.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Combined cycle power plant 2 Gas turbine plant 3 Steam turbine plant 4 Exhaust heat recovery boiler 5 Air compressor 6 Gas turbine combustor 7 Gas turbine 8 Superheater 9 Steam drum 10 Evaporator 11 Energy saving device 12 Casing 13 Control valve 14 Power generation Machine 15 Steam turbine 16 Condenser 17 Condenser pump 18 Feedwater pump 19 Fuel heating device 20 Combined cycle power plant 21 Gas turbine plant 22 Steam turbine plant 23 Exhaust heat recovery boiler 24 Air compressor 25 Fuel superheater 26 Gas turbine combustor 27 Gas Turbine 28 Generator 29 Steam Turbine 30 Condenser 31 Condenser Pump 32 Feedwater Pump 33 Superheater 34 Steam Drum 35 Evaporator 36 Energy Saving 37 Casing 38 Control Valve 39 Extraction Port 40 Turbine Bleeding System 41 turbine bleed recovery system 42 recovery port 43 turbine bleed control valve 44 thermometer 45 calculator 46 pump 47a first stop valve 47b second stop valve 48a first turbine bleed control valve 48b second turbine bleed control valve 49a first turbine bleed Temperature detector 49b Second turbine bleed air temperature detector 50a First turbine bleed air recovery stop valve 50b Second turbine bleed air recovery stop valve 51 Cooler 52 Cooling water system 53 Cooling water recovery control valve 54 Cooling water recovery system 55 Turbine bleed air thermometer 56 Computing unit 57 Cooling water control valve

Continued on the front page (51) Int.Cl. ⁶ Identification code FI F22B 1/18 F22B 1/18 C

Claims (19)

[Claims] 1. A combined cycle power plant comprising a gas turbine plant, a steam turbine plant and an exhaust heat recovery boiler, and a fuel heating device for heating fuel supplied to a gas turbine combustor of the gas turbine plant. A turbine bleed system for supplying turbine bleed air of a steam turbine of a turbine plant to the fuel heating device, and a turbine bleed gas recovery system for recovering turbine bleed air heated fuel of the fuel heating device to the steam turbine are provided. Combined cycle power plant. 2. A turbine bleed system includes a turbine bleed control valve, a computing unit that detects a fuel temperature at an outlet side of a fuel heating device, and controls opening and closing of the turbine bleed control valve based on a fuel temperature detection signal. The combined cycle power plant according to claim 1, further comprising: 3. A combined cycle power plant comprising a gas turbine plant combined with a steam turbine plant and an exhaust heat recovery boiler and comprising a fuel heating device for heating fuel supplied to a gas turbine combustor of the gas turbine plant. A turbine bleed air system that supplies turbine bleed air of a steam turbine of a turbine plant to the fuel heating device, and a turbine bleed air recovery system that recovers the turbine bleed air that has heated the fuel of the fuel heating device to a condenser of the steam turbine plant. A combined cycle power plant comprising: 4. A combined cycle power plant comprising a gas turbine plant combined with a steam turbine plant and an exhaust heat recovery boiler, and comprising a fuel heating device for heating fuel supplied to a gas turbine combustor of the gas turbine plant. A turbine bleed system for supplying turbine bleed air of a steam turbine of a turbine plant to the fuel heating device, and turbine bleed gas recovery for recovering turbine bleed air heated fuel of the fuel heating device to an outlet side of a condensate pump of the steam turbine plant Combined cycle power plant, comprising: 5. A combined cycle power plant comprising a gas turbine plant combined with a steam turbine plant and an exhaust heat recovery boiler and comprising a fuel heating device for heating fuel supplied to a gas turbine combustor of the gas turbine plant. A first turbine bleed system and a second turbine bleed system for supplying turbine bleed air of a steam turbine of a turbine plant to the fuel heating device, and the steam turbine recovers turbine bleed air heated by the fuel of the fuel heating device. A combined cycle power plant comprising a first turbine bleed air recovery system and a second turbine bleed air recovery system. 6. The first turbine bleed system is used to open a first stop valve during partial load operation to supply turbine bleed air to a fuel heating device from an upstream side of a steam turbine, while using a second turbine bleed system. The combined cycle power plant according to claim 5, wherein the bleed system is used when the second stop valve is opened during rated operation to supply turbine bleed air to the fuel heating device from a downstream side of the steam turbine. . 7. The first turbine bleed system includes a first turbine bleed control valve, matches a fuel temperature signal detected at an outlet side of the fuel heating device with a turbine bleed temperature signal, and when a deviation is found, 6. The combined cycle power plant according to claim 5, further comprising a computing unit that supplies a valve opening / closing signal to the first turbine bleed control valve based on the deviation. 8. The second turbine bleed system includes a second turbine bleed control valve, matches a fuel temperature signal detected at an outlet side of the fuel heating device with the turbine bleed temperature signal, and when a deviation is found, 6. The combined cycle power plant according to claim 5, further comprising a computing unit that supplies a valve opening / closing signal to the second turbine bleed control valve based on the deviation. 9. The first turbine bleed air recovery system includes a first turbine bleed air recovery stop valve, and the first turbine bleed air recovery stop valve is configured to perform valve opening / closing control in conjunction with the first stop valve. The combined cycle power plant according to claim 5 or 6, wherein 10. The second turbine bleed air recovery system includes a second turbine bleed air recovery stop valve, and the second turbine bleed air recovery stop valve is linked to the second stop valve to control valve opening and closing. The combined cycle power plant according to claim 5 or 6, wherein 11. A combined cycle power plant comprising a gas turbine plant combined with a steam turbine plant and an exhaust heat recovery boiler and comprising a fuel heating device for heating fuel supplied to a gas turbine combustor of the gas turbine plant. A first turbine bleed system and a second turbine bleed system for supplying turbine bleed air of the steam turbine of the turbine plant to the fuel heating device, and the turbine bleed heated fuel of the fuel heating device is recovered by the steam turbine plant. A combined cycle power plant comprising a turbine bleed air recovery system for recovery in a water dispenser. 12. A combined cycle power plant comprising a gas turbine plant combined with a steam turbine plant and an exhaust heat recovery boiler and comprising a fuel heating device for heating fuel supplied to a gas turbine combustor of the gas turbine plant. A first turbine bleed system and a second turbine bleed system for supplying turbine bleed air of the steam turbine of the turbine plant to the fuel heating device, and the turbine bleed heated fuel of the fuel heating device is recovered by the steam turbine plant. A combined cycle power plant comprising a turbine bleed air recovery system for recovery at an outlet side of a water pump. 13. A combined cycle power plant comprising a gas turbine plant, a steam turbine plant and an exhaust heat recovery boiler, and comprising a fuel heating device for heating fuel supplied to a gas turbine combustor of the gas turbine plant. A turbine bleed system for supplying turbine bleed air of a steam turbine of a turbine plant to the fuel heating device, a turbine bleed gas recovery system for recovering turbine bleed air heated fuel of the fuel heating device to the steam turbine, and a turbine bleed system. A provided cooler,
The cooling water supplied to the cooler is supplied to a cooling water system provided on the outlet side of a condensate pump of the steam turbine plant, and the cooling water obtained by cooling the turbine bleed air by the cooler is supplied to an inlet of a feed pump of the steam turbine plant. A combined cycle power plant comprising a cooling water recovery system for recovering the cooling water on the side. 14. The cooling water recovery system includes a cooling water recovery control valve, and an arithmetic unit that supplies a valve opening / closing signal to the cooling water recovery control valve based on a turbine bleed air temperature signal at an outlet of the cooler. 14. The combined cycle power plant according to claim 13, wherein: 15. A combined cycle power plant comprising a gas turbine plant combined with a steam turbine plant and an exhaust heat recovery boiler and comprising a fuel heating device for heating fuel supplied to a gas turbine combustor of the gas turbine plant. A turbine bleeding system that supplies turbine bleed air of a steam turbine of a turbine plant to the fuel heating device, and a turbine bleed air recovery system that recovers the turbine bleed air that has heated the fuel of the fuel heating device to a condenser of the steam turbine plant, A cooler provided in the turbine bleed system, a cooling water supplied to the cooler, a cooling water system provided on an outlet side of a condensate pump of the steam turbine plant, and a cooling water cooled turbine bleed by the cooler. Cooling water collected at the inlet side of the feed pump of the steam turbine plant A combined cycle power plant, comprising a recovery system. 16. A combined cycle power plant comprising a gas turbine plant, a steam turbine plant and an exhaust heat recovery boiler, and comprising a fuel heating device for heating fuel supplied to a gas turbine combustor of the gas turbine plant. A turbine bleed system for supplying turbine bleed air of a steam turbine of a turbine plant to the fuel heating device, and a turbine bleed gas recovery system for recovering the turbine bleed air heated fuel of the fuel heating device to an inlet side of a feed pump of the steam turbine plant And a cooler provided in the turbine bleed system, cooling water supplied to the cooler, a cooling water system provided on an outlet side of a condensate pump of the steam turbine plant, and turbine bleed cooled by the cooler. Cooling water is collected at the inlet side of the feed pump of the steam turbine plant. A combined cycle power plant comprising a cooling water recovery system for cooling. 17. A combined cycle power plant comprising a gas turbine plant combined with a steam turbine plant and an exhaust heat recovery boiler and comprising a fuel heating device for heating fuel supplied to a gas turbine combustor of the gas turbine plant. A first turbine bleed system and a second turbine bleed system for supplying turbine bleed air of a steam turbine of a turbine plant to the fuel heating device, and a first turbine for allowing the steam turbine to recover turbine bleed heated fuel of the fuel heating device. A bleed air recovery system and a second turbine bleed air recovery system, a cooler provided in the first turbine bleed air system and the second turbine bleed air system, and cooling water supplied to the cooler are supplied to a condensate pump of the steam turbine plant. A cooling water system provided on the outlet side and a cooling system that cools turbine A combined cycle power plant comprising: a cooling water recovery system configured to recover unreacted water at an inlet side of a feed pump of the steam turbine plant. 18. A combined cycle power plant comprising a gas turbine plant, a steam turbine plant and an exhaust heat recovery boiler, and comprising a fuel heating device for heating fuel supplied to a gas turbine combustor of the gas turbine plant. A turbine bleed system for supplying turbine bleed air of a steam turbine of a turbine plant to the fuel heating device, and a first turbine bleed system and a second turbine bleed system for supplying turbine bleed air of the steam turbine of the steam turbine plant to the fuel heating device A turbine bleed gas recovery system for recovering turbine bleed air heated fuel of the fuel heating device to the condenser of the steam turbine plant, and a cooler provided in the first turbine bleed system and the second turbine bleed system; Cooling water to be supplied to this cooler,
A cooling water system provided on the outlet side of a condensate pump of the steam turbine plant, and a cooling water recovery system for collecting cooling water obtained by cooling turbine bleed air with the cooler at an inlet side of a water supply pump of the steam turbine plant. Combined cycle power plant. 19. A combined cycle power plant comprising a gas turbine plant combined with a steam turbine plant and an exhaust heat recovery boiler and comprising a fuel heating device for heating fuel supplied to a gas turbine combustor of the gas turbine plant. A turbine bleed system for supplying turbine bleed air of a steam turbine of a turbine plant to the fuel heating device, and a first turbine bleed system and a second turbine bleed system for supplying turbine bleed air of the steam turbine of the steam turbine plant to the fuel heating device A turbine bleed air recovery system for recovering turbine bleed air heated fuel of the fuel heating device at an inlet side of a water supply pump of the steam turbine plant;
A cooler provided in the turbine bleed system, a cooling water supplied to the cooler, a cooling water system provided on an outlet side of a condensate pump of the steam turbine plant, and a cooling water cooled in turbine bleed by the cooler. A combined cycle power generation plant comprising: a cooling water recovery system for recovering water at an inlet side of a water supply pump of the steam turbine plant.